protected.test

* nsf.c (ObjectCmdMethodDispatch), protected.test: For ensemble (submethod) dispatches, since ever, call protection had not been enforced at all. This commit enables call protection (protected) for ensembles and adds basic tests. * nsfStack.c (GetSelfObj): To allow one to resolve the self reference at arbitrary callstack levels, separate GetSelfObj into GetSelfObj (macro) for the topmost self and GetSelfObj2.